In regions with deep fjords or unstable soils, engineers are designing floating bridges that rely on large, sealed steel pipe pontoons for buoyancy. These tubular pontoons-fabricated from 2.5 m diameter steel pipe sections-are arranged in arrays beneath the bridge deck, supporting both roadways and rail tracks. Norway's newest floating structure uses 72 pontoons, each comprising welded steel pipe compartments, to span 800 m across a deep-water channel.
In Washington State, retrofitting plans for the aging Hood Canal Bridge include replacing old concrete pontoons with corrosion-resistant steel pipe units. The steel pipe pontoons are easier to inspect via internal ROVs and incorporate ballast control systems to adjust buoyancy for changing loads and currents.
Japan's coastal road expansions on reclaimed land feature modular steel pipe pontoons filled with closed-cell foam, increasing safety in the event of hull breach. The modular pontoons interlock using flanged steel pipe collars, allowing rapid on-site assembly and future maintenance access.
Sweden's floating bridge technology now integrates wave-attenuating curtain skirts beneath the steel pipe pontoons to minimize movement. The skirted steel pipe array improves driver comfort and reduces stress cycles on the superstructure.
As coastal infrastructure adapts to climate change, steel pipe pontoons are emerging as a resilient, maintainable solution-enabling floating bridges to connect communities across challenging waterways worldwide.
